Carburetor

ABSTRACT

A carburetor for motor vehicle internal combustion engines in which an annular atomizing chamber is formed between two axially aligned circular walls which are axially slidable relatively to each other to vary the size of the atomizing chamber so that no individual throttle valve for the fuel mixture is required. The air for atomizing the fuel is conducted into the annular atomizing chamber by two axially aligned tubular conduits leading from opposite sides through the center portion of the circular walls where a spherical body is fixedly arranged and in whose hollow interior extends a needle-valve controlled fuel admitting tube, while fuel outlet apertures in the sphere discharge the fuel into the airstream which is caused to flow from the tubular conduits into the annular atomizing chamber through a short and narrow and adjustable passage formed between the surface of the sphere and the adjustable circular walls.

United States Patent [72] Inventor HugoSthmitz \eubeckumerstrasse 102.

472 Beckum. herman |21| Appl No 859.125 I22] Filed Sept. 18. I969 [45]Patented July 6. 1971 [3 21 Priority Sept. 28. 1968. June 21. 1969 [33]Germany [311 P1776 156.7andP1931 642.8

[54] CARBURETOR 15 Claims, 6 Drawing Figs. [52] US. Cl 261/29, 261/79,261/39, 261/44, 261/69. 261/62, 261/51 [51] lnt.Cl F02m 9/10 [50] Fieldof Search 261/29,

3,286,997 11/1966 Ledbctlerm v. 261/79 X 3,336.017 8/1967 Kopa .1 1261/79 X FOREIGN PATENTS 1.251832 2/1961 France. 261/79 PrimaryExaminer-Tim R. Miles Attorney-Singer, Stern and Carlberg ABSTRACT: Acarburetor for motor vehicle internal combustion engines in which anannular atomizing chamber is formed between two axially aligned circularwalls which are axially slidable relatively to each other to vary thesize of the atomizing chamber so that no individual throttle valve forthe fuel mixture is required. The air for atomizing the fuel isconducted into the annular atomizing chamber by two axially alignedtubular conduits leading from opposite sides through the center portionof the circular walls where a spherical body is fixedly arranged and inwhose hollow interior extends a needIe-valve controlled fuel admittingtube, while fuel outlet apertures in the sphere discharge the fuel intothe airstream which is caused to flow from the tubular conduits into theannular atomizing chamber through a short and narrow and adjustablepassage formed between the surface of the sphere and the adjustablecircular walls.

PATENTEUJUL 61971 3.591.148

sum 1 OF 5 ,4 da /re s PATENIED JUL em: 3591, 148

SHEET 2 OF 5 FIG. 3

INVEN TOR Hugo S072 mil? PATENIEU JUL 5:971

SHEET 3 OF 5 m wh w q ma m WA u H BY W PATENIED JUL 6197! 59 1. 148

sum 5 or 5 FIG. 6

INVENTOR Hu 0 ,Srbmzi BY 9 A ttomeys CARBURETOR The invention relates toimprovements in carburetors for the fuel of internal combustion engines.

lntemal combustion engines employ carburetors of the most differentconstruction. All of these carburetors, however, have in common that anair stream which is conducted past the end of a nozzle will draw fuelfrom the nozzle and this fuel, in view of the low pressure and the speedof the air, is atomized. There exists, however, a relationship betweenthe aspirated amount of fuel and the amount of air passing the nozzle orbetween the low pressure at the nozzle which is proportionate to theamount of air. In the event that the cross section of the atomizing zoneis not variable, the quality of the fuel preparation is increased ordrops in relation to the intermingled amount of air or the speed of theair respectively. Devices are known in which these facts are properlyconsidered, and which operate with an approximately constant lowpressure in the atomizing zone.

in carburetors of this type the tube cross section above the fuel nozzleis regulated by a slidable piston which is in connection with a lowpressure chamber in such a manner that when the low pressure increasesthe piston is raised so that the piston exposes a larger area of thecross section of the tube. At a reduced low pressure the piston dropscorrespondingly and the size of the free flow cross-sectional area inthe atomizing zone is reduced. The piston has secured thereto a conicalnozzle needle which follows the slidable movement of the piston andopens the fuel nozzle more or less. The control of the low pressure orthe intermingled amount of air, respectively, is effected by a throttleflap arranged after the atomizing zone. This throttle flap regulates thesize of the free flow cross-sectional area.

The disadvantage of these known devices, among others, is that the fuelis supplied point-shaped and, therefore, it can be treated only linearlyin the direction of the stream of air. in addition, the throttle flap,which is arranged immediately after the atomizing zone, splits the airstream into two partial streams so that, dependent upon the position ofthe throttle flap and the piston, the fuel in one or the other pressurestreams is given preferential treatment. This nonuniform distribution ofthe fuel in the air stream can also not be completely eliminated by aturbulence behind the throttle flap. The fuel introduction from thenozzle into the airstream and the further path of the fuel particles inthe airstream corresponds, when considered according to the flowtechnique, to a combination of source and parallel flow. (See Eek,Technical Flow Science, th Ed., FIG. 58, Page 57.)

The heretofore known carburetor constructions may produce an approximateuniform low pressure in the atomizing zone, but they fail to produce auniform distribution of the fuel in the airstream which is necessary toattain an optimum exploitation of the fuel and for reducing theheretofore customary CO contents in the exhaust gases of motor vehicles.

With a constant low pressure alone in the atomizing zone the problems ofthe known carburetor constructions are not eliminated. Around thethrottle flap, which is arranged directly after the atomizing zone, aregrouped a number of additional difficulties. The throttle flap, which isarranged in the prepared fuel-air mixture, first of all, separates thefuel-air mixture into two partial streams which, as a rule, can hardlycontain each the same amount of air-fuel mixture. Regardless of theopening condition of the throttle flap, there will always be caused aback pressure in the stream with an unsymmetric secondary flow andsecondary turbulences which are effective far into the air funnel and,therefore, prevent a uniform distribution of the fuel over the entirecross section of the stream. As a result of the produced unsymmetricalturbulences, which are particularly pronounced when the throttle flap isonly partially open, the fuel particles are thrown against the wall ofthe conduit and this leads to the well-known fuel film on the wall ofthe suction conduit. It is obvious that this fuel film consistspredominantly of the heavier atomizable particles of the fuel. When thethrottle is closed, this fuel film evaporates in view of the suddenlyincreasing low pressure. Owing to the lack of air, however, only anincomplete combustion of the fuel takes place, with the result that theexhaust gases contain very high amounts of CO.

it is an object of the invention to eliminate the disadvantages of theheretofore known carburetor constructions and to produce a carburetorsystem in which the preparation of the fuel does not take place linearlyin the direction of the flow of the air (two-dimensional) but takesplace spatially, namely, three-dimensional.

At the same time, the system of the present invention is provided withregulating and dosage devices which pennit a regulation of the amountsof combustion air and the fuel entering the motor without employing athrottle flap in the mixing tube that is, the motor output is notregulated by the amount of the mixture by a direct regulation of theamount of the combustion air when the same still is without fuel.

The air is the carrier agent for the fuel. If the combustion engine hasto deliver a predetermined output at the highest ex ploitation of thefuel, it is necessary to mix with the fuel a predetermined amount ofcombustion air, whereby the fuel has to be in a gaseous condition.Therefore, the air has not only the purpose of conveying the originalfluid fuel in any manner to the combustion chamber, but the air also hasto convert the fuel into a gaseous condition and must uniformlydistribute the fuel in the combustion air and then has to be conductedto the combustion chamber of the internal combustion engine. In ordernot only to atomize the original fluid fuel but to also vaporize thesame, substantially larger specific exchange surfaces are requiredbetween the combustion air and the f uel than are available in theconventional carburetors or in injection devices.

The realization of large specific interchange surfaces between thecombustion air and the fuel presupposes that the air and fuel moleculesare able to react with each other in a multilayer manner; that is theirdirection of movements and their speeds temporarily do not coincide witheach other. This may be accomplished by a source of turbulence for thecombustion air which, in the neighborhood of the core of the turbulence,is supplied with liquid fuel from a plurality of apertures. Thecentrifugal forces which decrease from the inside toward the outside andwhich also cause a decreasing angular speed of the airstream from theinside towards the outside act first of ali, upon the fluid particles ofthe fuel in the manner of a multilayer shear stream and cause a veryquick droplet resolution which is followed by a diffusion of the fuelmolecules so that a genuine spatial atomization of the fuel takes place.

Insofar as it is necessary for a fuel atomization to supply for theatomization thereof an additional amount of heat energy, thisrequirement can be met without difficulty since the required heatpotential is obtained by the thermic motor process. The proportionateevaporative cooling effect obtained by the improved atomization preventsa temperature rise of the fuel mixture and no loss of charge isexperienced by the motor cylinder.

Once the fuel is atomized, no danger exists any more that the fuel inthe suction lines leading to the motor will again separate from thecombustion airstream. The atomization of the fuel which already takesplace in the carburetor has the additional advantage that the individualmotor cylinders are supplied with a specific uniform mixture so that asa result the average specific engine output is improved. A furtherresult of the improved atomization and the resulting improved combustionis a reduction of the toxic portions in the exhaust gases of the motor.

The drawing illustrates a few embodiments of carburetors constructed inaccordance with the invention.

IN THE DRAWINGS FIG. I illustrates a longitudinal section of acarburetor having a rotational symmetric construction.

FIG. 2 illustrates across section along the line 2-2 of PK}. 1.

FIG. 3 illustrates one embodiment for the formation of a surface on aboundary wall for obtaining a substantial wall turbulence and forpreventing the formation of a fuel film on the wall.

FIG. 4 illustrates another embodiment of the carburetor of theinvention.

FIG. 5 illustrates an embodiment of the carburetor of the inventionintended for an automatic adjustment of the feed of the fuel in relationto the supplied amount of air, and FIGv 6 il lustrates a carburetor inaccordance with the invention which is provided with a special airsupply device.

Referring to the FIGS. l and 2, the air enriched with fuel leaves thecarburetor outlet 23 and is sucked in by the motor. The air, whenentering the carburetor, passes through the filters arranged on oppositesides of the carburetor housing and then passes through guide vane rings2i and with a twist enters the axially aligned suction tubes 26. Whenthe air paaes the centrally disposed displacement body 12 at the innerends of the tubes 26, it carries with it the fuel which is supplied bythe nonles l3 and the fuel is thereupon atomized in the annular chamberor tunnel 29, which extends concentrically about the common axis of thetubes 26 and is formed between two circular walls 2. The discharge ofthe fuel through the nozzles 13 is supported by the low pressure createdon the surface of the displacement body l2 and also by the superpressureexisting in the interior of the displacement body 12 which, to a smallextent is produced by the straight flowing airstream. The mixture offuel and air flows in the annular chamber 29 or tunnel alongspiral-shaped paths. ln view of the centrifugal forces which decreasefrom the inside to the outside, and also in view of the outwardlydecreasing angular speed of the air, large specific interchange surfacesor larger relative speeds are produced between the fuel particles andthe air particularly when the contact area of the walls 2 is providedwith a series of concentric steps 2a. This results in a particularlyeffective preparation of the fuel. The better, however, the fuelpreparation, the less danger filllSln that later on the fuel willseparate from the air in the suction line of the motor.

in order to attain for a predetermined cross section of the passage forthe required airstream in the atomization zone, the invention providesthat the circular boundary walls 2 forming the annular chamber 29 aremade adjustable so that the size of the cross-sectional passage isadjustable from a value zero up to a maximum value so that the fuel feedmay be adjusted in relation to the amount of air in the airstream. Thisadjustment can be accomplished by purely mechanical means as it isillustrated in the FIGS. 1 and 2. The adjustment may, however, also bemade in relation to the low pressure or in relation to the speed of theair at a point of the conduits which is suitable for measuring.

In the device illustrated by way of example in the FIGS. 1 and 2 of thedrawing, the fuel is supplied by a not illustrated fuel pump which isconnected to a pipe 9 leading to the fuel chamber 22 of the carburetor.This fuel chamber 22 is pro vided with an overflow regulator ll whichpermits the return flow of fuel by a pipe to leading to a suction linebetween the fuel supply container and the fuel pump. The nozzle tube 6is rigidly connected to one of the circular walls 2 of the annuiarchamber 29 and therefore is slidably adjusted with this wall 2. Theinlet end 7 of the tube 6 is conically enlarged and extends into thefuel chamber 22. The cone-shaped inlet end 7 serves as accelerating pumpwhen a quicker gas supply for the motor is required. By means of ajerklike rearward movement of the cone 7, which extends into a smallchamber 8, a short superpressure is produced in the chamber 8 whichresults in an accelerated feed of fuel into the hollow displacement body12 having a substantially spherical shape. An intermediate space isformed between the cone 7 and the outer boundary wall of the fuelchamber 22 so that the fuel, even when the cone 7 is erked rearwardiy,may flow freely into the nozzle tube 6.

The amount of fuel which flows toward the nozzle tube 6 requires a basicadjustment. This adjustment can be accomplished in various ways. Firstof all, with the assistance of the overflow device II which regulatesthe return flowing fuel. The more fuel is returned, the less fuelreaches the nozzle tube 6. This overflow adjustment may also take placein relation to an opening condition of the annular chamber 29 and alsomay take place in relation to the opening condition of the nozzle outletaperture in the displacement body 12 and also may take place in relationto the low pressure or the speed of the air at a suitable measuringpoint.

If, in view of sealing problems, one prefers to omit the axialdisplacement of the nozzle tube 6, then this tube 6 may be rigidlysecured to the fuel feed device. The fuel dosing then takes place byslidably adjusting the regulating needle 14. The opening condition ofthe nozzle tube 6 may also be adjusted in relation to the openingcondition of the annular chamber 29 for which purpose customary meansmay be employed or it may also take place in relation to the lowpressure or the speed of the air at a suitable measuring point. Theembodiment of the invention illustrated in the FIGS. 1 and 2 is providedwith a mechanical adjustment of the nozzle needle 14 in relation to theopening condition of the annular chamber 29. When the lever system 3,24, is operated it rotates the circular walls 2 about their tubularpivots which rotate in coarsely pitched threads 4 between the pivots andthe correspondingly threaded apertures in the walls 5 of the housing.This has the result that the circular boundary walls 2 are selectivelyaxially adjustable toward and away from each other and this results inan adjustment of the size of the cross section of the annular chamber.At the narrowest point the adjustment of the passage formed between thebody 12 and the walls 2 has a value which is zero and this value may beincreased to a maximum value. A shaft 30 is connected with the leversystem 3, 24 and is provided with a pin l9 which, in turn, actuates acam disc 27 for operating the lever 28 which performs an axialdisplacement of the nozzle needle 14 in the plane of the drawing. Theneedle 14 is slidably mounted in a tube 15 and the rear end of theneedle 14 extends into a cylindrical casing 18 containing a helicalspring 17 which surrounds the needle 14 and is arranged between thebottom of the casing 18 and a disc [6 fixedly attached to the needle 14.

The pitch of the cam disc 27 conforms to the different openingconditions of the annular chamber 29 and to the amounts of air which arepermitted to flow into this chamber 29 so that a slidable adjustment ofthe nozzle needle 14 in the nozzle tube 6 controls the amount of fuelwhich is required for the respective amount of air.

In order to avoid any sealing problems which may arise at the slidingfaces of the boundary walls 2 and the circumferential wall I, thepresent invention provides a further development in which the boundarywalls 2 are made of an elastic material or at least made partly of suchelastic material. The walls are then rigidly secured with their outerperimeter to the circumferential wall 1. Suitable pressure rings on therear faces of the boundary walls 2 having approximately a diameter whichcorresponds to the narrowest portion of the annular channel, are thenemployed for changing the cross section of the annular atomization zone29.

The shape of the boundary walls is not limited to the one illustrated inthe drawing in order to practice the invention. If desired, othercross-sectional forms may be employed, for instance, plane, concave, orconvexly curved.

Referring to the embodiment illustrated in FIG. 4, 31 is a fuel supplyline leading to the fuel pump 32 which conveys the aspirated fuel intothe pipeline 33 and into the fuel chamber 4] of the carburetor. The fuelchamber 4! is provided with a device for keeping the pressure constant.A portion of the fuel flows through the return line 34 back to thesuction side of the fuel pump 32.

Centrally between the two axially spaced and axially adjustable walls 44is fixedly arranged a sphere 46. This sphere 46 is provided with nozzleapertures 50 for the fuel and also with air ducts 47. When operating thegas pedal the two walls 44, with the assistance of not specificallydisclosed devices, are slidably axially adjusted so that the crosssection of the flow passages 42 and 43 are continuously varied. The twoelastic rings 45 on the outer circumference of the circular walls 44seal the inner space of the carburetor against the housing wall.

The air required for combustion, after passing air filters, enters thecarburetor housing at two oppositely disposed places A and enters with atwisting motion the interior of the carbu retor. The entering amount ofair is determined by the size of the cross-sectional area 42 formedbetween the outer surface of the sphere 46 and the rounded inner facesof the walls 44. The nozzle apertures 50 open at the narrowest point ofthe flow passages 42. A small portion of the centrally entering air isconducted by the air ducts 47, owing to the back pressure, into theinner space of the sphere 46 and there takes with it the fuel whichenters the sphere from feed pipe 40 and then combines again with themain airstream in the range of the flow passages 42.

The fuel dosing takes place with the assistance of the axially slidablymounted nozzle needle 49 whose slidable displacement is effected in apurely mechanical manner by part 48 in relation to the openingconditions of the two walls 44 or may also be effected with theassistance of known means in relation to the low pressure at a suitablemeasuring point, preferably in the central suction tube leading from theair filter to the carburetor.

The airstream revolving around the sphere distributes and atomizes,first of all, any liquid fuel still in the narrowest portion of the flowpassages 42. A further resolution of any still present very small fueldroplets takes place in the cross'sectional area 43. At this point thetwo partial streams come together. They revolve as a total streambetween the two walls 44 about the axis of the carburetor and at thepoint B they are drawn lengthwise into the suction pipes which lead tothe combustion chambers of the motor.

In view of the centrifugal forces within the revolving stream whichdecrease from the inside outwardly and in view of the likewisedecreasing angular speed of the stream of the fuel particles from theinside outwardly, the air acts as a multilayer shear stream so that acomplete resolution of the fluid fuel takes place and an absolutehomogeneously prepared fuel-air mixture is produced which leaves thecarburetor at B. This homogeneously prepared fuel-air mixture can not bebrought to dissociation because it is gaseous, even when subjected toperiodic oscillations of the air column in the suction conduit, so thatall the individual combustion chambers are provided with a qualitativeuniform mixture which improves the allover efficiency of the motor.

The atomizing principle of the invention, in addition to the advantagesof an improved fuel atomization, has additional advantages inconstructural regard and in the fuel control technique. The controlpossibilities produce an improved torque characteristic and also afavorable CO emission of the motors installed in motor vehicles, wherebyalways an optimum relation is automatically maintained between theamount of air necessary for combustion and the amount of fuel therebyassuring at the same time genuine vaporization of the fuel.

in the embodiment of the device of the invention as illustrated in FIG.5, the regulation of the fuel feed or the slidable adjustment of thefuel regulating needle 49, respectively, is ac complished with theassistance of a measured value transducer 51. The amount of air passingthrough the filter 52 is measured in the central suction tube betweenthe air filter and the carburetor at 53 or a measured value equivalentto the amount of air is entered into the measured value transducer 51which in turn transmits regulating pulses corresponding to this measuredvalue to the fuel dosing device. The measured value transducer 5] mayalso consist of a pneumatically actuated adjustment member or mayconsist of an electronic computer with an attached mechanical adjustmentmember which in addition to the measured value which is equivalent tothe the amount of air, considers additional factors which influence theoperation of the motor, such as the temperature, barometric pressure,humidity and the like, and transmits correspondingly corrected controlpulses to the fuel dosing device. In similar manner, the shut-off of thefuel feed takes place when the vehicle is decelerated and an enrichmentof the fuel mixture takes place with the assistance of the measuredvalue transducer when the motor has to start when it is cold.

In the embodiment of the device illustrated in FIG. 6, a mechanicallydriven air blower is arranged in front of the carburetor whicheliminates any charge losses resulting from fuel flow losses at fullload.

The air drawn in at 54 and passing through the filter 52 is acceleratedor receives a pressure increase by the rotor 56 driven by a motor 55. Anadjustment flap 59 causes a more or larger portion 58 of the airstream57 which leaves the rotor casing, to flow through a bypass tube 60 backinto the filter 52. If now the pedal 61 is depressed, the adjusting flap59 is closed, the bypass tube 60 is also closed so that a larger amountof air can flow to the carburetor. The amount of air which is conductedinto the carburetor, or its equivalent measured value taken at 53, isconverted by a measured value transducer 51 into an adjusting pulse andis transferred to the fuel regulating needle 49 and to a mechanicaladjustment member 62. The fuel regulating needle doses the fuel feedproportional to the amount of air passing through the carburetorv Themechanical adjustment member 62 acts upon the levers 63, 64 and 65 andupon the adjustable walls 44 shown in FIG. 4 in such a manner that thesame are axially slidably adjusted and adjust the size of the passage 42to such a value that the speed of the air in this passage is independentof the amount of air and is always approximately constant.

The mechanical adjustment member 62 may also be con structed in such amanner that it operates directly in proportion to the air pressure at 53in order to effect an adjustment of the walls 44.

The rotor 56 assists the pistons of the engine to draw the mixture intothe combustion chambers and this assures a substantially improvedfilling of the cylinders particularly at full load compared with adevice in which the fuel mixture is solely drawn into the cylinders bythe low pressure produced by the downward moving pistons.

What I claim is:

l. A device for preparing atomized fuels, comprising a housing, meansforming in said housing a variable atomization zone comprising anaxially symmetrical structure including two parallel walls formingbetween the same an annular tunnel for receiving the atomized fuel,means for connecting said atomization zone with an air supply means,means for adjusting the cross section of said atomization zone inrelation to the amount of fuel required, means for feeding separatelyair and fuel to the center of said atomization zone, and means fortangentially discharging the prepared atomized fuel from said annulartunnel, said means for adjusting the cross section of said atomizationzone including at least one of said walls, means for axially adjustablymounting said wall, and means for axially adjusting said wall relativelyto the other for changing the cross section of said atomization zone.

2. A device according to claim 1, including means for regulating theamount of fuel which is introduced centrally into said atomization zonein relation to the adjusted size of crosssectional area of said annulartunnel.

3. A device according to claim I, including means for regulating thedosage of said fuel which is centrally introduced into said atomizationzone in relation to the low pressure in said zone.

4. A device according to claim 1, including means for regulating thedosage of said fuel which is centrally introduced into said atomizationzone in relation to the amount of air passing through said zone.

5. A device according to claim I, in which the means for supplying fuelto the center of said atomization zone is provided with means forreturning some of said fuel to the place of supply in relation to theamount of air required for atomization of the amount of fuel in saidatomization zone.

6. A device according to claim I, in which at least one of said axiallyadjustable walls is provided with an annular elastic portion which isfixedly connected to a circumferential wall of said housing of saidcarburetor.

7. A device according to claim 1, including a hollow displacement bodyarranged between said two walls at the center thereof, means forsupplying fuel to the interior of said body, said body being providedwith a nozzle aperture communicating with said atomization zone.

8. Device according to claim 1, including means for regulating theamount of the prepared fuel mixture which is conducted to an internalcombustion engine in relation to the pressure measured between thedevice and said engine.

9. Device according to claim 1, including a fuel dosing means and anelectronic computer which in accordance with the amount of air passingthrough said annular tunnel produces a control pulse which actuates saidfuel-dosing means.

10. Device according to claim 1, including a fuel-dosing means and anelectronic computer which in accordance with the amount of air passingthrough said annular tunnel produces a control pulse which actuates saidfuel-dosing means, said computer including means for rendering effectiveother factors such as temperature, barometric pressure and humiditywhich modify the atomized fuel which is tangentially discharged fromsaid annular tunnel.

ll. Device according to claim 1, including a fuel dosing means and anelectronic computer which in accordance with the amount of air passingthrough said annular tunnel produces a control pulse which actuates saidfuel-dosing means, said computer including means for controlling the admission of an additional amount of fuel required for starting a coldengine and also being adapted to close down the feed of fuel when theengine is to be made inoperative.

12. A device according to claim 1, including a mechanically operated airblower connected with said air supply means.

13. A device according to claim I, including a mechanically operated airblower connected with said air supply means, the output of said blowerbeing connected with an air input tube leading to said atomization zone,and a valve controlling a branch pipe leading from said air output tubeto the input side of said blower, said valve controlling said branchpipe being adjusted by a manually operable foot pedal.

14. A device according to claim 1, including means for axially adjustingsaid two walls relatively to one another in relation to the low pressureproduced by the air admitted to said atomization zone at the point wherethe fuel is introduced into said zone.

15. A device according to claim 1, including means for axially adjustingsaid two walls relatively to each other in relation to the amount of airadmitted into said atomization zone.

1. A device for preparing atomized fuels, comprising a housing, meansforming in said housing a variable atomization zone comprising anaxially symmetrical structure including two parallel walls formingbetween the same an annular tunnel for receiving the atomized fuel,means for connecting said atomization zone with an air supply means,means for adjusting the cross section of said atomization zone inrelation to the amount of fuel required, means for feeding separatelyair and fuel to the center of said atomization zone, and means fortangentially discharging the prepared atomized fuel from said annulartunnel, said means for adjusting the cross section of said atomizationzone including at least one of said walls, means for axially adjustablymounting said wall, and means for axially adjusting said wall relativelyto the other for changing the cross section of said atomization zone. 2.A device according to claim 1, including means for regulating the amountof fuel which is introduced centrally into said atomization zone inrelation to the adjusted size of cross-sectional area of said annulartunnel.
 3. A device according to claim 1, including means for regulatingthe dosage of said fuel which is centrally introduced into saidatomization zone in relation to the low pressure in said zone.
 4. Adevice according to claim 1, including means for regulating the dosageof said fuel which is centrally introduced into said atomization zone inrelation to the amount of air passing through said zone.
 5. A deviceaccording to claim 1, in which the means for supplying fuel to thecenter of said atomization zone is provided with means for returningsome of said fuel to the place of supply in relation to the amount ofair required for atomization of the amount of fuel in said atomizationzone.
 6. A device according to claim 1, in which at least one of saidaxially adjustable walls is provided with an annular elastic portionwhich is fixedly connected to a circumferential wall of said housing ofsaid carburetor.
 7. A device according to claim 1, including a hollowdisplacement body arranged between said two walls at the center thereof,means for supplying fuel to the interior of said body, said body beingprovided with a nozzle aperture communicating with said atomizationzone.
 8. Device according to claim 1, including means for regulating theamount of the prepared fuel mixture which is conducted to an internalcombustion engine in relation to the pressure measured between thedevice and said engine.
 9. Device according to claim 1, including a fueldosing means and an electronic computer which in accordance with theamount of air passing through said annular tunnel produces a controlpulse which actuates said fuel-dosing meaNs.
 10. Device according toclaim 1, including a fuel-dosing means and an electronic computer whichin accordance with the amount of air passing through said annular tunnelproduces a control pulse which actuates said fuel-dosing means, saidcomputer including means for rendering effective other factors such astemperature, barometric pressure and humidity which modify the atomizedfuel which is tangentially discharged from said annular tunnel. 11.Device according to claim 1, including a fuel dosing means and anelectronic computer which in accordance with the amount of air passingthrough said annular tunnel produces a control pulse which actuates saidfuel-dosing means, said computer including means for controlling theadmission of an additional amount of fuel required for starting a coldengine and also being adapted to close down the feed of fuel when theengine is to be made inoperative.
 12. A device according to claim 1,including a mechanically operated air blower connected with said airsupply means.
 13. A device according to claim 1, including amechanically operated air blower connected with said air supply means,the output of said blower being connected with an air input tube leadingto said atomization zone, and a valve controlling a branch pipe leadingfrom said air output tube to the input side of said blower, said valvecontrolling said branch pipe being adjusted by a manually operable footpedal.
 14. A device according to claim 1, including means for axiallyadjusting said two walls relatively to one another in relation to thelow pressure produced by the air admitted to said atomization zone atthe point where the fuel is introduced into said zone.
 15. A deviceaccording to claim 1, including means for axially adjusting said twowalls relatively to each other in relation to the amount of air admittedinto said atomization zone.